Nurse poisons patients to die on someone else's watch

A Japanese nurse who may have killed dozens of elderly patients wanted to ensure that her terminally ill victims died anytime but on her watch, due to the "nuisance" of facing relatives with tragic news, Japanese media reported.

The nurses worked in pairs, Asahi Shimbun reported, and Kuboki would administer the deadly chemicals while her colleagues were busy in briefings as shifts changed over.

Kuboki was arrested on Saturday on suspicion of killing Sozo Nishikawa, 88, who died in September 2016. She also admitted poisoning 88-year-old Nobuo Yamaki, who was being treated in the same room as Nishikawa.

Several days after security cameras were installed at the hospital following the deaths of Nishikawa and Yamaki, the cameras caught Kuboki walking in the hospital while carrying a box containing insulin, a drug used to decrease blood glucose levels of patients with diabetes.

"It would be troublesome if that responsibility fell on me", Kuboki said.

The chemical, an antibacterial that's readily available within hospitals, was found in Yamaki's body and his IV bag.

Security cameras caught a former nurse, under arrest on suspicion of fatally poisoning a patient at a hospital here, walking inside the institution while carrying unnecessary drugs during a night shift after the incident, investigative sources said. Another, who worked alongside Kuboki at a different hospital, said she was "considered competent", although she was "the kind of person who was hard to figure out".

Investigators found tiny punctures in the rubber seals of the bags, indicating that the antiseptic had been injected into them.

The deaths also coincided with a series of incidents that police suspected had been carried out by a member of the hospital's staff, but were unable to prove.

When police investigators checked all uniforms worn by nurses in charge of the patients on the fourth floor, they found the antiseptic on only one uniform - that worn by Kuboki - around the pocket.

Police questioned Kuboki in late June after she quit the hospital. At least 48 patients died at the hospital in suspicious circumstances over a three-month period in 2016, Japanese newspaper Asahi Shimbun reported. Kuboki reportedly confessed to murdering at least 20 other patients out of the 48 that passed away between July and September 2016.

Kuboki's former co-workers said they were shocked to hear about the nurse's arrest.